

      Views with greater magnification are impressive and 
      can show more detail.   They also need far more rays!

      TO ZOOM

      1)  First run an 'ordinary' simulation.  If not 
          already done, this can be a fast "Black dots on 
          white" version.   It does not matter whether 
          the simulation is central or offset.

      2)  For convenience, hide the Control Panel and 
          from the Menu bar click 'Zoom',  'Show Zoom Box'.     

          The zoom menu options are only enabled when
          there is a view to zoom.

          Drag and resize the Zoom Box until it contains 
          the view wanted.  The zoom box will always
          resize itself so that its proportions are those 
          of the full screen.

      3)  Once the area wanted is selected, leave the 
          zoom controls alone.
 
          Only cancel the zoom box if you wish to run 
          a normal unzoomed simulation instead.

      4)  Reshow the Control Panel.  Choose the graphics 
          (e.g. grey scale), simulation conditions and 
          sky characteristics needed.

          Remember to increase the number of rays by
          roughly the square of the magnifiction used.

      5)  Start the simulation.  Alternatively, leave
          the Control Panel hidden and start the zoomed
          simulation from the Menu bar 'Run','Start'.


      The zoom box will disappear and the new simulation 
      will be of the area inside the last zoom box 
      position but now occupying the full screen.

      The maximum zoom is about 12X

      The zoomed view can be stored as usual.  The view 
      can be further zoomed.    Ray filtering and ray 
      tracing can be done with zoomed views.

      The zoom settings are stored with simulation
      parameters. 

      Return to normal view via the zoom menu control 
      otherwise any further simulations will also be 
      zoomed.   

